ubuntu使用官方的apt-get来安装软件，官方源的速度过慢。
但是使用阿里云的源就不一样了，也不会存在很多问题，下面为笔者总结一下怎么更换ubuntu的软件源。

一，备份
#cd /etc/apt/
#sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak

二，修改
#sudo vim /etc/sources.list

将sources.list中全部替换为如下内容
deb http://mirrors.aliyun.com/ubuntu/ trusty main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ trusty-security main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ trusty-updates main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ trusty-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ trusty main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ trusty-security main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ trusty-updates main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ trusty-backports main restricted universe multiverse

三，更新
#sudo apt-get update